Method and apparatus for casting plate glass



` 2 Sheets-Sheet 1 F. E. TROUTMAN Er AL.

METHOD lmp APPARATUS' Foa CASTING PLATE GLASS Filed April 13,

Oct. 6, 1925.

FIG. 1

FIG. 3

oct. 6,1925.

v F. E. TRQUTMAN Er AL IETHOD AND APPARATUS FOR CASTINGPLATE GLASAAS Filed April 13; 1522 2 Sheets-Sheet 2 VE TORS Patented-oct. 6,- v1925.

UNIITEDy lSTATES l 1,556,381 PATENT oI-'F'lcE--A FRANK EL, TROUTMAN AND CHARLES n. CHRISTIE, oF BUTLER, PENNSYLVANIA.

METHOD AND-APPARATUS FOR CASTING PLATE GLASS.

Application led April 18, 1922'. Serial No. 552,340.

To all 'whom t may concer/n v Be it known that we, FRANKA E. TROUTMAN and CHARLES H. CHRISTIE, citizens'of the United States, and residents of Butler, in

the county of Butler and State of `Pennsylvania, have invented a new and useful Improvement in Methods and Apparatus for Casting lPlate Glass; and we do hereby declare the following to be a full, clear, and

exact description thereof.

Our invention relates to the art of casting plate glass and has special reference to the methods and apparatus describedand claimed in our copending applications Serial l5 Nos. 295,485 and 295,486, filed May 7 1919,

and Serial No. 525,327, iiled December 28, 1921, wherein the glass to be cast is drawn from. a tank or other suitable source into a discharge receptacle having a downwardly opening discharge outlet and having a valve or plunger' which is adapted to close the olitlet when in its lowest position and which, when raised, permits the glass to flow through the. outlet in a vertical column which is received upon a movable casting table and is then rolled into a sheet.

In practicing this method it is found that, even though the glass outlet and the plunger are very carefully constructed and matched, acertain amount of glass will dribble out around the edges of the outlet lwhen the plunger is seated. The small strings of glass resulting from this dribbling action remain hanging around the edges of the" outlet and may be carried down with the next charge of glass, thereby impairing the quality of the glass.- Small fragments of dirt produced by the grinding action of the plunger upon the outlet and composed of the fire clay of which the plunger and the outlet member are constructed, may also be dislodged and carried down with these dribbling streams or with the outer portions of the descending column of glass, and when such fragments are carried into the finished glass they of course impair its quality.

. It is one ofthe objects of our presentinvention to dispose of any such dribblings'of glass as may escape from the. outlet when Ytheplunger is seated, and also tocatch and dispose of any impurities such as fire clayv fragmentsthat may come through the outlet.

Another object of our invention is to provide improved means for insuring that each.

char eliof glass shall issue from the-.outlet and fall upon the casting table with a clean .member is such that it ts loosely within the discharge outlet, leaving a small space around its upper edges through which dribbling glass will descend. A iiange'extends out around the tubular portion of, the dribble catcher to a diameter greater than the `diameter ofthe discharge outlet and serves as a shelf to insure that the descending dribbles of glass will be caught and held.

The dribble catcher not only has the func-- tion of catching the dribbles of glass which -may issue between the casting operations,

but also provides an auxiliary discharge throat fon@ the glass during the casting operation. ble catcher is arranged to cause a portion of the issuing glass to adhere to its surface. This adherence may be promoted by heating the dribble catcher, or by providing projections on its inner surface, or by both of these means. `Wfhen the plunger is raised and glass starts'- to descend, the first portions of glass which roll down over 'the edges of the outlet'will come upon the heated surface of the throat portion of the dribble catcher and willadhere, forming a glasslined dischargethroa'tI through which the remainder of the glass passes on its way to the casting-table. -Since the glass which reaches the casting table has never been in contact with anything except a portion of the glass itself, and since the glass-lined interior of the discharge throat has no chilling effect upon it, the leading end of the glass which reaches'the' casting table isperfectly clean and hasaregular rounded shape, this shape being prodii'fced' by the checking effect which the dribblei'icatcher. has on ythe outside of 4the glass, and which permits the inner part of the glass to flow faster than the sides of the column, instead of lagging behind the sides and forming a concave end,.' asis the case when the glassis merelyallowed to ow through the usual bushing'. v

',Ihe tubular portion of the dribpanving drawings,

The adhesion of the outer portion of the issuing glass also serves to catch and hold any dirt or other impurities that may start down with the leading end of the glass when the lunger rises. The portions of glass which carry these impurities are the portions which lirst engage and adhere to the dribble catcher, thus holding the impurities in place and preventing them from issuing with the dischar edyglass.

One desirable way o carrying our invention into practice 1s shown in the accomin which Fig. 1 is a vertical sectional central view through the discharge portion of the casting apparatus; Fig. 2 is a bottom plan view o` the const-ruction shown in Fig. 1; Fig. 3 is amend elevational view showing the dribble catcher swung to one side of the outlet; and Figs. 4

to 10, inclusive, are diagrammatic vertical sectional views showing the successive stages in which the apparatus is operated.

Fig. 1 of the drawing shows the discharge portion of a glass receptacle which may be a tank constructed and arranged with a runway as shown in our above-mentioned c0- pending applications, or lmay be any other' Suitable container for the molten glass that is to be cast. In this figure the numeral 2 represents the bottom of a runway which' vmay 'conduct the glass from the tank, as

shown in our'said prior ap lications, and

jwhich communicates with a discharge chamber 3 having vertical lside walls 4 and a downwardly dconverging bottom portion 5 in which, is seated a bushing 7 having a dischar'g'eo ening 8 which may be circular or o f any ot er desired outline. A plunger 9 is .arranged vertically above 'the outlet 8 and ma vbe'provided with a downwardly curved en A1() adapted to seat in and close the discharge outlet 8. The Aplunger 9 is arran ed v to be raised and lowered by' suitable mec anism whichis not shown, since this mechamsm ma be of well known construction.

The disc arge chamber 3 may be covered with insulating material, as' shown at 11", and issurplorted upon suitable metal framework 12. e bushing 7 is held in place by means of a dat rin 13 which is secured beneath-the 'discharge'c amber by`means of'bolts 14.

The parts thus far described are .shown only'forthepurpose of illustratingv our inl constructed in avar the urpose of catching the glass that may `dribb e out around the sides .of 'the discharge'o ning 8 while this cgiening is closed by t e unger9, and also or the purpose of. regu ating the ilow of glass to produces.

smooth' leading end, wev provide an annularf `member 15 which we term 'a dribble catcher,

" and which, as shown, .consists of a tubular .shell having downwardly. converging' sides whichht lwithin a corresponding opening 1,5se,sa1

per portion ofthe shell 15 is of the proper diameter to iit loosely within the discharge outlet 8, leaving a small s ace-18, and when in the position shown in ig. 1 the ange 17 extends beyond the edges of the outlet 8 and is close to the underside of the bushing 7.

The shell 15 may, if desired, be provided with projections 19 which may be struck up from the sides of the shell, and which assist i1111 ciliusing glass to adhere to the sides of the s e The support 16 is carried by an arm 20 which is removably fixed in a socket member 21 which, in turn, is supported by an arm 22 pivot'ed at 23 to a` vertically adjustable hanger 24 suspended from abracket 25 which is secured to the underside of the the metal sheathing 26 ofthe discharge chamber. yThe arm 22 is extended beyond the pivot 23v and carries an adjustable wei ht 27 which ten -to hold the arm 22 in its orizontal position,

member 21. The fork 28 is suspended by the :Eork 28 beneath the socket.

means of bolts 30 from the' ring 13. The.

vertical adjustment of the hanger 24 is proyduced by means of a screw-threaded shank 31 which extends through a screw-threaded opening in the bracket 25 and is secured in its adjusted position by means ofnuts 32.

Fig. 3 shows in dotted'lines thel position of the dribble catcher-when itis'swung-to one side of the discharge opening. 'Flamelfrom va burner 35 may be directed into the interior ofthe dribble catcherl for the purpose of heating it suiciently to Icause glassto admay be 'secured bymeans of one 01";1more .here' toits surface.- In .order to retain' the"v heat within the dribble catcher, a cover36 o 1 bolts to the underside of the sheathin'g';

and may 'extend'outwardly in such position 'as `to fit over the-upper edge of the shell -15 when the device .is'swung into the position j of Fig. 3. -v p The operation of this device may be best understood by- `referring in turn to Figs. 4

'to.-10. Fig. 41showsl the condition-whenfthe plunger 9 1s seated in the opening-.8,butnot I tightly enough' to revent the esca e of small streams of (glass `.whicli, 'event ou h the plunger an the bushings. dass.' .amai

bushing-are very carefu y iiti ted,- ow down around the edges of the outv lBefore'th'e descend through the space 18 between thev bushing and the shell 15 and adhere to the outside of the shell 15 or are caught on the flange 17. A

Fig. 6 shows the condition of the glass just after the plunger 9 begins to. rise. `A small portion of the glass may flow into the space 18 around theshell 15, carrying with it any dirt or small fragments of fire-clay that may have become dislodged at the edges .of the glass outlet. Then the glass adjacent to the bushing flows down around the lower'` end of the plunger in an-annular body, as

shown at B, Fig. 6 and enters the upper end of the shell 15. This shell has preferably been heated before being placed in position, and the outside portion ofthe glass B adheres to the shell 15, as shown at B', Fig. 6, and holds with it, any impurities that are present.

The glass continues toV flow through thev outlet as the plunger continues to rise, and the central portion C descends at a faster rate Vthan the side portions D, thus roduc# ing the appearance shown in'Fig. The

"central portion of the glass continues to descend'at a faster rate than the'sides, prov ducing the somewhat indented appearance shown at E, Figi 8, and'finally the'rounded appearance shown at F`,'Fig. 9 where the central portion of the glass has caught up with the side portions a-nd has passed them.

As 'the downward flow of glass continuesnthe sides of the shell 1.5.are .completely covered by adhering glass G, and the central por-A tion of ,the stream issues, as -shownJ at H, Fig. 10. It will be observed that this issuing glass has never come in contact, after entering the discharge loutlet 8, with any substance except the glass adhering to the vinner walls of the shell 15. Therefore the issuing glass is cleanand hot, and .forms the even, rounded leadingfend H as shown in AFig.- 10. The glass thus set in motion flows v'fdownj ina vertical column and is preferably received on aI moving casting table, as described in our above-mentioned prior ap-i plications..

' After the proper quantity of glass is discharged, the plunger 9 is again lowered until its lower end seats in the discharge outlet 8,

and the flow of glass is thus cut ofi'. The key 29 is then knocked out and the dribble lcatcher isswung down and to one side of the'glass outlet, as shown in Fig. 3, where it is replaced by another similar device which,

has previously` been -cleaned andA heated. The used dribble catcher may be cleaned by immersing it in water to chill the adhering glass and then breaking this glass away.

The shell 15 of the dribble catcher may -`be made of refractory material instead, of

metal, but we find it most convenientt'o make this shell of metal, and to -heat it just before it is placed in position beneath the vent the layer of adhering glass from being melted and washed off by the flowing stream. If desired, the radiation of heat may be increased by means of additional flanges or fins or even by artificial cooling applied after the flow of glass begins, vbut such added cooling means are not ordinarily required.

The sides of the dribble catcher may converge downwardly, as shown, or may b e cylindrical, and if the sides are made converging the angle of convergence may be varied in vaccordance with the nature of the glass, the size of the outlet, and the shape which it is desired to impart to the column of glass as it descends toward the casting table.

Instead of making the dribble catcher removable, as shown, it may obviously be built in around the glass outlet, and may be cleaned ofi' between casting operations by means of a flame. In this case, the glasslined discharge throat may be composed of glass that is quite fluid, this glass being -held in an annular recess in the nature of a trap, formed below the upper edge of the discharge opening 8, and the impurities being caught in this recess at the beginning of the casting operation.

The details of-constructionherein shown may be also varied in many other respects without departing vfrom our invention, the

scope of which is set forth in the appended 'glass and solidifying a portion of'said glass to 'form an annular discharge throat, and discharging another portion of glass .through the said glass-lined discharge throat 'upon a casting table. i A

casting plate glass that 3. 'The method of comprises flowing the ,glass through a downwardly opening outlet and thence through a heated annular member, thereby causing a portion of'the glass to adhere to /said member, and to form a glass-lined ydischarge `throat for the issuing glass.

4. 'The method ofV castmg plate glass that fos comprises flowing the glass through a downwardly opening outlet and thence through an annular member having downwardly converging sides, and capable of causing glass to adhere to its surface, thereby forming a glass-lined discharge throat for the issuing glass.

5. The method of casting plate glass that comprises placing the glass in a rece tacle having a downwardly opening `disc arge outlet, closing said outlet from above, and bringing beneath said outlet 'a member adapted to catch the glass that may dribble out around the edges of said outlet.

6. The method of casting plate glass that comprises placing the glass in a rece tacle having -a downwardly opening disc arge outlet, closing said outlet from above, andv bringing beneath said outlet an annular member adapted to catch the glass that may dribble out around the edges of said outlet.

7 The method of casting plate glass that comprises placing the glass in a receptacle having a downwardly opening discharge outlet, closing said outlet from above, bringing beneath said outlet an annular member, opening said outlet, and permitting the glass to flow through said annular member upon a casting table.

8. The method of casting plate glass that comprises placing the glass in a receptacle having a downwardly opening discharge outlet, closing said outlet from above, bringing beneath said outlet an annular member to which a portion of the descending glass will adhere, thereby forming a glass-lined discharge throat, Aopening the said outlet, and permitting the glass to flow through said annular member upon a casting table.

9. The method of casting plate glass that comprises placing the glass in a receptacle having a downwardly opening discharge outlet, closing said outlet from above, bringing beneath said outlet a metal annular member to which a portion of the descending glass will adhere, thereby forming aglass-lined discharge throat, opening the said outlet, and permitting the glass to 'low through/said annular member upon a casting table.V

10. The method of casting plate glass that comprises placing the glass in a receptacle having a downwardly opening discharge outlet, closing said outlet from above, bring.- ing beneath said outlet an annular member having means for catching glass that may dribble through said outlet and composed of material to which lass will'adhere, thereby forming a glass-lined discharge throat for the issuing glasspopening the said-outlet, and permitting the glass to flow through said annular member upon a casting table.

11. The method of casting/plate glass that comprises placing the glass in a receptacle having, aI downwardly opening discharge outlet, closing said outlet fromabove, inserting into saidv outlet from beneathan 'an- ,nular member fitting loosely in said outlet,

openingsaid outlet and permitting the glass to flow through said annular member upon a casting table.

12. The method of casting plate glass that comprises placing the glass 1n a rece tacle having a downwardly opening disc arge outlet, closing said outlet fromabove, inserting into said outlet from beneath an annular member fitting loosely in said outlet, and having dribble-catching means on its outer side, opening said outlet and permitting the glass to flow through said annular member upon a casting table.

13. The method of casting plate glass that comprises placing the glass 1n a receptacle having a downwardly opening discharge outlet, closing said outlet 4 from above, inserting into said outlet from beneath a heated annular member fitting loosely in said outlet', opening said outlet and permitting the glass to flowthrough said annular member upon a casting table.

14. The method of casting plate glass that comprises placing the glass in a receptacle havingA a downwardly opening discharge outlet, closing said outlet from above, inserting into said outlet from beneath a heated annular member fitting loosely in said outlet, and having dribble-catching means on its outer side, opening said outlet and permitting the glass to flow through said annular member upon a ycasting table.

15. The method ofocasting plate glass that comprises placing the glass in a receptacle having a downwardly opening discharge outlet, closing said outlet from above, bring beneath said outlet an annular member to which glass will adhere, o ening said outlet, permitting the glass to ow through said annular member upon acasting table, yclosing said outlet, removing said annular mem`-. ber, and replacing said annular member with another similar member.

- 16. The method of casting plate glass that '11 comprises placing the glass in a receptacley having a downwardly' opening discharge outlet, closing the saidfoutlet from above, inserting into said4 outlet from beneathV an. annular member fittingloosely in said outle't, and capable of causing glass to adhere to its surface, opening said outlet, permitting the glass ta flow through said outlet upon a casting table, closing said outlet, re moving said annular member, and replacing said annular member. with'another similar member.

17. The method of casting plate glass that comprises placing theglass in a receptacle havingy a downwardly opening discharge outlet, closing said outlet from above, insertin into said outlet from bemeans on its outer side, the said member glass.

being Capable of causing glass'to adhereto its surface, opening said outlet and permitting the glass to flow through said member upon a casting table, closing said outlet, removing said annular member, and replacing said annular member with a similar member.`

18. Apparatus for casting plate glass comprising al glass rece tacle having a downwardly opening out et, a valve for causing glass to issue from said outlet, and means for forming av portion of said glass into a discharge throat for the following portions of glass,

19. Apparatus for casting plate glass comprising a glass receptacle having a downwardly opening outlet, a valve for causing glass to issue from said outlet, and means for checking the descent of the sides of the issuing glass and for chilling a portion of said glass to form an annular disclarge throatI for the following portions of ass. 20. Apparatus for casting plate glass comprising a glass receptacle havingv a downwardly opening discharge outlet, means for closing said outlet from above, and an annular member adapted to be placed removably beneath said outlet and td form a discharge throat for the issuing g ass.

21. Apparatus for 'casting plate glass com rising a receptacle having a, downwar lyopening discharge outlet, means for closing said outlet from above, and an annular member adapted to be placed removably beneath said outlet and capable of causing glass to adhere to its surface, ,thereby forming a glass-lined' discharge throat for the issuing glass. 4

22. Apparatus for casting plate glass comprising a glassl receptacle having a downwardly opening discharge outlet, means for closing said outlet from above, and an annular metal member adapted to be placed removably beneath said outlet and tti form a discharge throat for the issuing g ass.

23. Apparatus for casting plate glass comprisin a glass receiptacle having a downwar `y v"opening ischarge outlet,

means for closing said outlet from above,

and a heated annular member adapted to be placed removably beneath said outlet and to form a discharge throat for the issuing -24. Apparatus for -casting plate glass comprising a glassreceptacle having a downwardly openingv discharge outlet, means for closing said outletfrom above,

an annular metal member adapted to beV placed removably beneath said outlet and to 'form a dischar e throat for the issuing glass, and means or heating said member.

25. Apparatus for casting plate glass i downwardly i discharge throat for the issuing glass.

`26. Apparatus for casting plate glass Y comprising a glass receptacle having a downwardly opening discharge outlet,

\means for closing said outlet from above,

and a heated annular member having downwardly converging 'sides adapted to be placed removably beneath said outlet and to ftlirml a discharge throat for the issuing' ass. g 27. Apparatus for casting plate glass comprising a glass receptacle having ,a opening discharge outlet, means for closing said o utlet from above, and an annular metal member having downwardly convergin sides adapted to be placed removably l(beneath said outlet and to form a discharge throat for the issuing glass, and means for heating said member.

28. Apparatus for casting plate glass comprising a glass receptacle having a downwardly opening discharge outlet, means for closing said outlet from above, and an annular member having projections on its 'inner surface adapted to be placed removably beneath said outlet and to form a discharge throat for the issuing glass.

29., Apparatus for casting plate glass comprising a glass receptacle having a downwardly opening discharge outlet, means for closing said outlet from above,

and an annular metal member having projections -struck up on its inner surface and 'adapted to be placed removably beneath said outlet and to forma discharge throat for the issuing glass.

30. Apparatus for casting plate glass 'comprising a glass receptacle having a outlet,

adapted tobep aced removably beneath said4 outletand to erm a discharge throat for the issuin glass.

31. pparatusfor casting plateglass comprising a glass receptacle vhaving a downwardly opening discharge outlet, means for closing said outlet from above, and means for catching glass that mayv dribble out around the edges of said outlet. 32. Apparatus for casting plate glass comprising a glass. receptacle having a downwardly opening discharge outlet, means for closingl said outlet from' above, and means .for catching glass that may dribble out Aaround the edges of said outlet, said4 dribble catching means comprising a member adapted tolbe removably applied beneath said outlet and having a lange extending L beyond the edges of said outlet.

33. Apparatus Jfor casting plate glass comprising a glass rece tacle having Ia downwardly opening disc arge outlet, means for closing said outlet from above, and means for catching glass that may dribble around the edges of said outlet, said dribble catching means comprising an annular member fitting loosely in said outlet and having a fiange onits outer surface, the said flange v y prlsing a glass rece tacle havlng a ydownextending beyond ythe edges of said outlet.

34.' Apparatus for casting plate glass comprising a glass receptacle having a downwardly opening disc arge outlet, means for closing said outlet from above, and means for-catchin glass that may dribble around ythe edges o said outlet, said dribble catching means comprising an annular metal member fitting loosely in said outlet and having a flange on its outer surface, the said flange extending beyond the edges of said outlet.

35. Apparatus for casting plate glass comprising aglass receptacle having a downoutlet.

an annular memberv wardly opening discharge outlet, means for closing said outlet from above, and means for catching glass. that may dribble around. the edges of said outlet, said dribble catching means comprising an annular sheetmetal member-having downwardly converging sides tting loosely in said outlet and having a flan e on its outer surface, the said fiange exten ing beyond the edges of said 37. Apparatus for casting /plate glass comprising a glass receptacle having a downwardly opening discharge outlet, means for closing said outlet from above, and means for catching glass that may dribble around the edges of said outlet, said dribble catching means comprising an annular sheetmetal member having downwardly converg- ,ing sides and having projections formed on its inner surface fitting loosely in said outlet and having a ange on its outer surface, the said ange extending beyond the edges of said outlet.

38. Apparatus for casting plate glass comprising a glass receptacle having an outlet surrounded with fire clay, a plunger havin a lire-clay surface adapted to seat in said outlet, and an annular metal `member having its upper end received in said outlet and spaced from the walls thereof.

In testimony whereof we, the said FRANK E. TROUTMAN and CHARLES H. CHRISTIE. have hereunto set our hands.

FRANK E. TROUTMAN CHARLES H. \CHRISTIE. 

